Double C-Shaped Reactive Shielding Coils for Low EMF and High Efficiency Wireless Power Transfer System

This paper proposes double C-shaped reactive shielding coils to alleviate the efficiency degradation caused by the reactive shielding method. Using the proposed method, higher power transfer efficiency and EMF shielding performance than the conventional reactive shielding coil can be achieved. The main idea of the proposed shielding coils is to create an additional inner loop by making the shielding coil into two C-shaped loops. In the inner loop of the proposed shielding coils, current flows in the same direction as that of transmitting coil to amplify the magnetic field. In the outer loop, current flows in the opposite direction to cancel the leakage magnetic field. In this paper, the wireless power transfer system with the proposed shielding coils is designed and verified through 3D electromagnetic and circuit simulation.